This revised application requests support for a program of research on neurocognitive processes underlying speech and language outcomes in prelingually deaf children following cochlear implantation. Past research on cochlear implants has been narrowly focused on speech and language outcomes and efficacy of cochlear implantation as a medical treatment for profound hearing loss. As noted in the two previous NIH consensus statements on cochlear implants, little, if any, basic or clinical research has investigated the underlying neurobiological and neurocognitive factors that are responsible for the enormous individual differences and variability in the effectiveness of cochlear implants. The primary objective of this research project is to demonstrate that domain-general neurocognitive processes related to executive functioning, such as working memory, fluency-speed, concentration-inhibition and organization-integration skills, are strongly associated with traditional clinical speech and language outcome measures. These executive function/cognitive control processes involve the global coordination, integration and functional connectivity of multiple underlying brain systems used in speech perception, production and spoken language processing. In two related projects, we test the hypothesis that executive function and organization- integration (EOI) processes contribute an additional unique modality-independent source of variance to speech and language outcomes above and beyond the traditional demographic, medical and educational factors. The first project uses a cross-sectional design to assess EOI functioning in long term cochlear implant users;the second project uses longitudinal methods to investigate the development of EOI functioning. The new findings obtained from this project on the underlying sources of variability in spoken language processing will help clinicians and researchers understand, explain and predict individual differences in speech and language outcomes following cochlear implantation. The results of this project have direct clinical implications for improving the diagnosis, treatment and early identification of young deaf children who may be at high risk for poor speech and language outcomes following cochlear implantation. PUBLIC HEALTH RELEVANCE: The enormous variability in speech and language outcomes of deaf children who receive cochlear implants is a significant clinical problem. The proposed research project on neurocognitive processes in deaf children with cochlear implants will provide new fundamental knowledge about the sources of variability and underlying neurocognitive factors that are responsible for individual differences in speech and language outcomes. These findings will have direct implications for the diagnosis, treatment and early identification of deaf children who may be at high risk for poor outcomes following implantation.